Three-piece can

ABSTRACT

A can model is provided for processed or non processed foods, for use by food companies or others. The model includes a three-piece can, which has a conical shape with a top and a bottom having different diameters, but within limits not to compromise rolling on flat surfaces and guides, minimizing friction between the external part of the cylindrical body with the finish or artwork while rolling. The can may also be stacked, since it is provided with different diameter top and bottom, which fit in each other when stacked.

FIELD OF THE INVENTION

The present invention relates to a can model for processed or non-processed foods, for use by food companies or others.

BACKGROUND

Cans for foods and other uses comprising three pieces with welded cylindrical bodies, seamed by a mechanical process at their upper ends by a top and at their lower ends by a bottom of same shape, are already known in the art. Said cans may optionally be provided with rims in the cylindrical body to reinforce it, allowing the use of thin sheets.

There are two basic types for such cans:

Three-piece cans with top and bottom of same diameter

These cans are made of welded cylindrical bodies (tubes), which are calendered and welded into the final diameter of the can, then receiving conventional processes of flap formation, beading and closing the top or bottom according to clients' requirements. One example of this kind of can is shown in FIG. 1 of the state of the art.

Three-piece cans with tops and bottoms having different diameters

These cans are made of welded cylindrical bodies (tubes), calendered and welded in the final diameter of the can, with an additional process of diameter reduction on one of the ends of the tube (necking), then followed by conventional processes of flap formation, beading and closing the smaller diameter bottom, allowing stacking of filled cans due to the difference between top and bottom diameters. One example of this kind of can is shown in FIG. 2 of the state of the art.

With the advent of sterilization in continuous rotating autoclave (cooker cooler), the two types of cans mentioned above have shown some substantial inconveniences for their processing:

Three-piece cans with top and bottom of same diameter

In this case, the rolling process of cans used in the continuous rotating autoclave is easily performed, and the body of the cans (tube) may be previously printed, with no loss in print quality after the rolling process. However, this solution impedes correct stacking, since the cans do not fit the others.

Three-piece cans with smaller top and larger bottom in diameter with diameter reduction at one of the ends of the tube (necking)

These cans have the advantage of being easily stacked. The neck-in is made on the can by the hanging of one of the ends of the can whose single objective is to improve stacking. To prevent the can from rolling around its own axis due to the big difference between the top and the bottom of the can, an additional rim (reinforcement) on the body near the smaller bottom is required, so that the friction during the process allows the can to be rolled in the continuous sterilization system without damaging the body of the can. In this case, excessive friction damages the artwork, finish and/or tin from the body of the can at that reinforcement point. Due to this problem, the can is only labeled after the process, creating additional processing steps and lowering process speed. Furthermore, due to its smaller diameter top, this kind of can is more difficult to open with conventional can openers because of the neck formed in the cylindrical body at that point to fasten the smaller top, which makes correct placement of the opener more difficult.

SUMMARY

Bearing the above in mind and in order to overcome the mentioned problems, the present invention has been developed. It includes a three-piece can, with cylindrical shape with a top and a bottom of different diameters. One of the ends undergoes an expansion process (increase in diameter or neck-out), but within certain limits not to compromise its rolling on flat guides and surfaces minimizing friction of the external part of the cylindrical body having a finish or artwork while rolling. Said cans may also be stacked, since they are provided with tops and bottoms of different diameters which fit in one another when stacked.

This embodiment of the can solves the aforementioned drawbacks, since the expanded cylindrical shape of the assembly allows for appropriate flexibility during use, meeting various forms of use of stackable cans with the artwork already printed on the cylindrical body, especially in automatic thermal processing equipment of continous rotating types (e.g. cooker cooler) wherein rolling of the can is required. The can of the present invention provides the advantage of allowing the end user to open the can at either of its end with a conventional can opener, usually at the cleanest end due to the piling up.

BRIEF DESCRIPTION OF DRAWINGS

To better visualize the present invention, the attached figures are presented as examples, not limiting the present application, wherein:

FIG. 1 is a partial cross section view of a conventional three-piece can with top and bottom of same diameter;

FIG. 2 is a partial cross section view of a conventional three-piece can with top and bottom of different diameters, with reduced diameter at one of the ends of the tube (necking);

FIG. 3 is a partial cross section view of a can according to the present invention;

FIG. 4 is a view of a stack of cans of the present invention;

FIG. 5 is a detailed view of a can rolling over a flat surface, showing the lack of contact between the body of the can (tube) and the surface due to the existence of a gap.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The object of the present invention will be disclosed based on the above listed figures given as examples, but not limiting the scope of protection of the present invention, where the final can will be generically indicated as L.

The object of the present application includes a can L, made of a welded body (1), which is initially cylindrical and which afterward has one of its edges expanded (neck-out), said body (1) optionally provided with reinforcement rims in its body (2) when the metal sheet to form the body (1) is thin.

The can L is preferably made of tinplate and/or chrome-plated steel, appropriately finished and printed with the artwork defined by the user. The cylindrical body 1 is formed by the conventional process of plate cutting, formation of the body, calendering and welding. Initially, the body (1) is built with the base dimension (smaller), the tube is expanded in a conical shape forming the flange (flap) and subsequently the rims for radial reinforcement of the can (2).

Can L has an upper closing having a conventional or easy-to-open top (3) and a conventional or easy-to-open bottom (4). Said top (3) or bottom (4) is seamed at one of the ends according to the needs of the user. When seamed, said top (3) and bottom (4) form upper (5) and lower (6) ends that support the body of the can when it is rolled.

Said ends (3, 4) have different diameters, being that the difference between them should be in a range between 2 and 6 mm. Said difference between diameters defines a range A, which as a function of the height C of the can L will provide an angle θ. Said angle θ should be within the range from 0.5 to 2° for the can to roll without rotating around its own axis.

As an example, the table below shows the ratio between the diameter of the top (3), bottom (4), height C and angle θ in relation to market conventional sizes:

Top (3) Bottom (4) Height (C) Angle θ 73 70 83 1,035 73 70 92 0,934 73 70 95 0,905 99 96 118 0,728 127 124 135 0,637 155 152 152 0,565 155 152 178 0,483 155 152 226 0,380

The conical can is sent to the user with one of the ends (larger or smaller) already seamed according to the client's requirements and/or tooling in the client's plant to close the cans after product filling.

If the user makes use of continuous rotating equipment (e.g. cooker cooler), the rolling of the can L without harm to its body (1) is guaranteed by the support given by the upper (5) and lower (6) edges, which create a gap as shown in FIG. 5.

The present utility model presents several advantages to the conventional models, such as the cans may be processed in continuous rotating autoclave systems (e.g. cooker cooler systems), the cans may be stacked, and, since the cans are expanded cans, less steel is used in their manufacture, thus lowering manufacturing costs and sale price of the metal container.

In addition, the user will not need tooling adaptations, since the closing process is conventional and the tops and bottoms used are those already abundant on the market.

The proposed conical can, with said construction, may be made in diverse sizes and capacities to meet different needs of users of this kind of packaging. 

What is claimed is:
 1. A three-piece can comprising a cylindrical body (1) with rims (2), a top (3) and a bottom (4), wherein said cylindrical body (1) is expanded into a conical shape (1), provided with a top (3) having a first diameter, and a bottom (4), having a second diameter greater than the first diameter, the top and bottom (3, 4) being of a conventional or easy-to-open type, said top (3) and bottom (4) diameter differences ranging from 2 to 4 mm, forming an angle on the wall of the expanded body (1) from 0.1 to 2°, said top (3) and bottom (4), when seamed, create support edges (5, 6) for the can L to be rolled on flat surfaces. 